Do any of you use slow growth plant or pumpkin fertilizer?

From what I gather, it won't extend your watering time, but makes your harvest take longer to grow. I don't understand why this would be helpful at all? xD;

If you have a current use or idea, please let me know!

(PS- If you currently use these- I'll give you all of my slow growth fertilizers, if you want them! *first come first served, forum post only*) I was about to delete them but thought I'd ask and see if anybody else had caught onto something I hadn't n_n